In our prior U.S. Pat. No. 5,882,118 and its divisional method U.S. Pat. No. 6,068,584, we disclosed and claimed the attachment of advertising strips to T-shirt bags and a method for accomplishing such attachments during the course of fabricating such bags from extruded plastic tubing. Because the bags disclosed in our prior patent were heat-sealed along both their bottom and top edges, it was possible simultaneously to heat seal the ends of advertising strips to be attached to the bag along both the top and lower edges of such strips. These strips could be disposed either within the gussets of the bags or along an outside edge.
Attachment of advertising strips in the manner disclosed in our prior patents, however, cannot be accomplished where the top edges of the bag, such as those sometimes referred to as handle bags, flat bags and merchandise bags are left open at their top edges in order to enable merchandise to be placed in the bag. One type of such bags may have a central handle in contrast to the side handles of the T-shirt bags. When such open top edge bags are being produced, it is not possible to drop heating elements on each side of the cutting blade, transversely along the bag's division line and simultaneously heat seal the bottom of one bag and the top of the adjacent bag with the upper end of the advertising strip since the top edges of each bag must remain open. If it is, therefore, desired to provide open top edge bags with advertising strips, it is necessary to find some means and/or method for attaching the upper end of the advertising strip to the sides of one or both of the bag walls.
When advertising strips are attached to shopping bags there is sometimes a problem of movement of the strips with respect to the bags when the strips are secured only at the strip ends. For this reason it is necessary to develop methods for securing the strip to the bag walls between the strip ends.